Method and apparatus for washing and treating silica



R. H. MOORE.

METHOD AND APPARATUS FOR WASHING AND TREATING SILICA- APPLICATION FILED AUG.Z9, I917- Patented Jan. 25, 1921.

A TTORNE YS.

INVENTOR. flMM WITNESS:

PATENT OFFICE."

new H. oons. or BERKELEY, CALIFORNIA.

METHOD AND- ArrAnATus iron WASHING, AND TREATING-SILICA.

Specification of Letters Patent Patented; J a 25, 1921 Application filed August 29, 1917. Serial No. 188,728. i

To (ill whom it may concern Be it known that I, RA P H... Moonn, a citizen of the United States, residing at iierkeley, in the county of Alameda and State of California, have invented certain new and useful Improvements in Methods and Apparatus for lVashing and Treating Silica, of which the following is a specification.

The present invention relates-to a method oi? washing and refining silica, and to an apparatusfor carrying out the various steps of said method.

The object of the invention to refine a natural ore which contains silica and kaolin, to extract these two constituents in substantially pure form, and to this end the inven-.

tion comprises broadly a method of washing the ore and agitating the same in the presence of water to break up the kaolin and to free the same from the grains of silica, and to then. float off the kaolin in the water. By means of my invention. I am enabled to treat a natural product contain.- ing about 30% of clay and about 65% silica and to recover both products in a substan-.,

tially pure state, thefiinal sand containing approximately 97% silica. The clay as recovered is of a very high grade and; may be used commercially; The silica is also of a high grade and is, well adapted foruse in making glass, a use which requires an extremely high-grade product almost absolutely free of clay or other impurities.

I am aware that changeswithin the scope of the claims hereto appended may be made in the various steps of my method. and in the details of construction of the apparatus for carrying out themethod as ishereinai'ter described and illustrated, without in any manner departing from the spirit of, the invention.

With this in view, the invention. will now be described with reference to the accompanying drawings, wherein-.

Figure 1 is a plan view of a preferred form of apparatus for carrying. out my invention. a I

Fig. 2 is a sectionalelevationof the same taken on'the line 2+2 of Fig. 1, and viewed in the direction of the arrows.

In the drawings, the reference numeral 1 designates a body of orewhiflh is being mined. The ore as dug out from this body, is dumped into a sluice-box 2 and therein mixed with water and allowed to flow clay adhering to the silica.

through a trough or flume to a pump 4, by whiclrit is elevated through a pipe 5 and dumped into a mixing or washing tank 6.

In this tank the material is violently agitated by a rotary paddle 7 to break up the ore and to remove the major portion of the The material, which is now in the form of a thin mud, is allowed to run out of the mixing tank 6 through a comparatively coarse screen 8, and into. the lower portion of a triple elevator 9. An overflow pipe 10 conducts the liquid portion of the mud out of the elevator prising three endless slat conveyors 18 running over end drums l4 and and provided with downwardly projecting slats or flights 16 adapted to operate in close relation with inclined troughs or floors 17. These conveyers, as; will be clearly seen from the drawings, collect the silica and the heavier portions oi'the solid material-from the bottom of the elevator tank 9 and carry the same up along the inclined troughs 17 and dump the same into a transversely disposedjand slightly inclined trough 18.

From the trough. 18 the material flows intoa rotary screen 19, in which the larger particles are removed and discharged through a trough 20 while the finer particles are allowed to fall through into 'a second mixing tank 21*. The interiorof the rotary screen'l9 is. sprayed and washed by a; jet of water issuing from a pipe 22'. Inn-the mixing tank 21 the. sand is again agitated. by a paddle 23 in the presence of water' and a further portion of the adheringclay is broken up-and removed thereby. An overflow outlet 24: allows. the liquid, with thelighter kaolin suspended therein, to be. led out of said tank 21 and to be returned througha pipe 5 to the lnice bQXZ. The am unt of kaolin carried off by this washing is so small that no attempt is made to recover the same from the water, but it is allowed to mix tary washer with the unwashed material in the, sluice boX 2 and to be carried through the initial mixing tank 6.

'The heavier, portion of the material in the tankZl is carried out of said tank by an elevator 26. formed in a manner identi-m "cal with'the previously described elevator,

ence of water and stillniore oi? the adher-' ing kaolin is removed theretrom and is carried out with the water through an overflow outlet into a pipe 31 from which it is preferably returned by a pump 32 and a pipe 33 into the first mixing tank 6. A third elevator 3d, constructed similarly to the previously described elevators, carries the heavier sand upout of the third washing: tank 27 and dumps the same into a roi-k jet of water issuing from a nozzle washes the sand during its elevation by the third elevator'3el. In the rotary washer 35 the sand is again agitated and washed in water within a tank Bland the inal portion or the adhering kaolin is removed therefrom and allowed to pass out through an overflow outlet 38 and a pipe 39 into the pipe 31'. 'rrjet of washing water issuing from a nozzle 40 is allowed to play uponthe interior of the rotary washer 35, said nozzle beingsupplied by a pipe ll with water from any convenient source, not shown in the drawings. The pipe d1 also eer-nee to be understood that the sluice-box 2 may be located inany position convenientto the body of ore l which is being mined or excavated, andpn ay be moved about to follow the'zregion of excavation ofsuch material. Therbody of the apparatus however,

the

involving the various members between first washing tank-6 and the final conveyer permit sired.

42, is intended to be permanently located, the liume 3 or the pipe being extensibleto thesluice box Qto be moved as do- It will also be readily understood from the foregoing description that my process consists broadly in. breaking up the'crude material into its component parts, aMmely,

sand and clay, by means of "violent agitation in water. The clay being the more iin'ely divided or the two materials, is carried oil in suspension in the washing water, while the sand is picked up from the bottom'ot the tank and conveyed out by" mechanical means. 3y means of a number Oif repetitions or this process practically all the clay is removed from the sand and bothcan be recovered in a substantially pure condition. 7 Having thus described my invention what I- claim as new and desire to protect by Letters Patent is r 1. In a classifier of the "character described, a tank provided with a sorting comsupplies the nozzles 22', 28 and 36, as shown in the drawings.

The washed sand, which is almost pure silica discharged from the upper end of therotary washer 35 onto any suitable means for conveying the same to any desired place or deposit; shown this means as comprising a belt conveyor/indicated at 4-2 and adapted to deposit the clean sand into a discharge hopper 43. The water issuing from theupper end of the rotary washer 35 and running oil the belt conveyer -l2 is caught in a tank 44: surrounding the lower portion of said con- -eyer'and provided with an overflow outlet pipe 46 into the return pipe 31.

It is to be understood, that any suit-able mean'smay be'provided for operating the various movable partsof the apparatus de' scribed above, namely, the pumps, the agitating paddles, the elevators, the rotary screen and'the rotary washer. It is also 7 l5 from which said water is led through a in the drawings, 1 have -partment, stirring means in said compartment for agitating the pulp, said compar ment lSGID pl'ovicleclivitili an overflow, and an ndependently operated endless conveyer 'in-the tank dipping intothesortingcompertinent and terminating to one side of the'stirr ng means for conduct ng thecoarse sandsjfrom said sorting compartment to a point above the surface of the pulp in the tank; V

2; In a classifier of the character described, a tank provided with sorting compartment, stirring means in said. compar ment foragitating the pulp, said compartment being provided with an overflow, an independently operated endless conveyer in thetank dipping into the sorting-commit mentj and terminating to one side of the stirring means for 'conductingthe coarse sands from said sorting compartment to a'point above the surface of the pulp in thet'ank, and means for washing the coarse sands as the same are conducted from said compartment.

lOO

Intestimony-whereof I have signed my 7 two subscribing witnesses.

S. (lemmas.

name to this specification in the presence of 

